1. Field of the Invention
The present invention relates to an image forming apparatus having a collecting sorter for collecting and sorting transferred sheets and a recyclic automatic document feeder (RADF). The present invention also relates to a controller for controlling an operation of the image forming apparatus.
2. Description of the Related Art
A general collecting sorter has two functions. A first function is a sorting function for arranging transferred sheets discharged from an image forming apparatus in a page order of an original. A second function is a collecting or stacking function for arranging the transferred sheets for every page of the original. In the case of the sorting function, an operator inputs the required number of copies by an input means in advance so that the transferred sheets are discharged onto each of bins disposed in the sorter by the same number as the number of sheets of the original.
In the general image forming apparatus, when the same original is copied and copies thereof are distributed to each of business sections or divisions, required copying numbers are different from each other for every business section or division. Accordingly, it is impossible to cope with such a situation by using the above two functions. Therefore, there is a problem that an operator must count the number of transferred sheets and sort them for every business section after sheets are transferred and completely discharged.
For example, an apparatus for solving such a problem is shown in Japanese Patent Application Laying Open (KOKAI) No. 60-128462. In this apparatus, the number of copies for every distributing place written on an original is read by a light-receiving element and data about this copying number are inputted to a central processing unit (CPU). An apparatus of the sorter section in the central processing unit (CPU) is controlled such that the transferred sheets are discharged to each of the bins in accordance with these data. However, in such a structure, it is necessary to add a light-emitting element and a light-receiving element as hardware to the image forming apparatus and write the number of copies onto the original. Therefore, the structure of the image forming apparatus is complicated and cost thereof is increased and it is very troublesome to operate the image forming apparatus. Further, in the above publication, there is no description about a method for arranging the transferred sheets when the original is constructed by a plurality of sheets.
In general sorting systems, the cost of an entire copying system is increased and a copying machine having each of such sorting systems is disadvantageous in comparison with the general copying machine having a copying machine body cheaply manufactured.